In laparoscopic surgery, access is gained to an interior surgical site by making one or more short incisions in the body which extend down to the interior surgical site, and then inserting a hollow tube or cannula into each incision so that the cannulas can act as liners to hold the incisions open and thereby provide portals leading down to the interior surgical site. A laparoscopic procedure can then be performed by passing surgical instruments (e.g. cutting devices, clamps, viewing apparatus, etc.) down the cannulas so that the distal working ends of the instruments can be positioned and used about the surgical site, while the proximal handle ends of the instruments remain outside the body where they can be grasped by the surgeon.
Laparoscopic procedures frequently involve the removal of tissue from the interior surgical site. For example, one of the most common laparoscopic procedures practiced today is the laparoscopic cholecystectomy, in which the patient's gallbladder is removed from the body. In other laparoscopic procedures, other tissue (e.g. an appendix, portions of the intestine, etc.) may be removed from the body. In some situations, the excised tissue is relatively small and can be passed through the narrow cannula opening intact. In other situations, however, the excised tissue is too large to fit through a cannula intact. When this occurs the excised tissue must generally be cut down into a number of smaller pieces before it can be passed through a cannula. For example, in many laparoscopic cholecystectomies, the patient's gallbladder must be dissected into several smaller pieces before it can be removed through a cannula.
Such dissection of the excised tissue can present problems for the surgeon. For one thing, the excised tissue must generally be held in place by one instrument (e.g. a forceps) while it is dissected into several smaller pieces by another instrument (e.g. a cutting tool). These smaller pieces of tissue must themselves be captured by apparatus so that they can be removed from the body. It can be difficult to coordinate the holding, dissecting and capturing of the various pieces of tissue, particularly during laparoscopic surgical procedures where visibility is generally limited and tissue access restricted.